Am.  Jour.  Pharai.l 
September,  1897.  / 
Ge hemic  Acid. 
445 
condenser  for  several  hours,  then  the  reaction's  product  was  poured 
into  an  excess  of  water,  the  precipitate  formed  thoroughly  washed, 
dried  and  crystallized  from  alcohol.  This  compound  forms  needle- 
like anhydrous  crystals,  which  melt  at  i  8o°  C.  The  number  of 
acetyl  groups  (C2HsO)  entering  this  compound  was  determined  by 
saponifying  a  weighed  quantity  in  an  excess  of  normal  alcoholic  po- 
tassium hydrate,  and  then  titrating  back  the  excess  of  alkali  by 
means  of  standard  hydrochloric  acid.  Assuming  that  the  two  hy- 
drogen atoms  of  the  hydroxyl  groups  have  been  replaced  by  two 
acetyl  radicals,  we  have  the  following  : 
C13H9  (C2H30)205,  calculated  percentage  of  (C2H30)2.  Found. 
25-98  25-14 
On  adding  bromine  to  a  hot  solution  of  gelsemic  acid  in  glacial 
acetic  acid  a  voluminous,  white  precipitate  formed,  which,  when 
crystallized  from  alcohol,  formed  yellow  needles  which  fused  at  2500 
C.  A  further  investigation  of  this  body  was  postponed  for  lack  of 
material. 
Thus  far,  from  the  above  results,  we  may  ascribe  to  gelsemic  acid 
the  formula  C13H903  (OH)2.  Considering  the  active  reducing  char- 
acter of  this  principle  it  is  highly  probable  that  either  an  aldehyde 
or  a  ketone  group  is  also  present,  which  further  investigation  will 
determine.  That  gelsemic  acid  is  identical  to  aesculin,  as  Robbins 
and  others  have  assumed  (disputed  by  Wormley),  is  not  possible,  as 
the  comparisons  and  criticisms  of  the  combustions  already  given 
have  shown.  In  addition  to  this,  further  comparisons  are  given 
below.  It  may  be  possible  that  a  relationship  in  certain  groupings 
exists  between  these  two  principles,  which,  however,  cannot  be  set- 
tled as  yet.3 
3  "About  fifteen  years  ago  I  prepared  for  and  presented  Professor  Fiiickiger 
with  a  quantity  of  pure  white  crystallized  gelsemic  acid.  Professor  Fiiickiger 
became  much  interested  in  its  chemistry  and  personally  prepared  some  aesculin 
to  compare  therewith.  He  determined  that  they  were  different  bodies,  advis- 
ing me  of  the  fact  by  letter,  stating  that  he  would  continue  the  investigation,  in 
which  he  was  deeply  interested.  The  subject,  however,  rests  among  his  un- 
completed works,  and,  so  far  as  I  know,  he  did  not  publish  his  results." — From 
a  personal  letter  from  John  Uri  Lloyd,  dated  August  16,  1897,  after  this  paper 
was  written. 
